Electrostatic jamming devices and methods of making such devices

ABSTRACT

At least some embodiments of the present disclosure direct to an electrostatic sheet jamming device formed by a sheet having a conductive layer and a dielectric layer. The jamming device includes a first section of the sheet, the first section being separated from the sheet, and a second section of the sheet, the second section being separated from the sheet. The sheet is non-extensible and flexible. The first section and the second section are slidable relative to each other in a first state. The first section and the second section are jammed with each other in a second state when a voltage is applied between a conductive layer of the first section and a conductive layer of the second section.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Application No. 62/691,456,filed Jun. 28, 2018, the disclosure of which is incorporated byreference in its/their entirety herein.

TECHNICAL FIELD

The present disclosure is related to jamming devices that can be usedfor motion resistance.

SUMMARY

At least some embodiments of the present disclosure direct to anelectrostatic sheet jamming device formed by a sheet having a conductivelayer and a dielectric layer. The jamming device includes a firstsection of the sheet, the first section being separated from the sheet,and a second section of the sheet, the second section being separatedfrom the sheet. The sheet is non-extensible and flexible. The firstsection and the second section are slidable relative to each other in afirst state. The first section and the second section are jammed witheach other in a second state when a voltage is applied between aconductive layer of the first section and a conductive layer of thesecond section.

At least some embodiments of the present disclosure direct to a methodincluding the steps of: retrieving a sheet having a conductive layer anda dielectric layer; separating a first set of sections from the sheet;connecting the first set of sections electrically via a first connector;separating a second set of sections from the sheet; connecting thesecond set of sections electrically via a second connector; andassembling the first set of sections and the second set of sections intoa jamming device. The sheet is non-extensible and flexible. The firstset of sections and the second set of sections are slidable relative toeach adjacent pair in a first state. The first set of sections and thesecond set of sections are jammed together in a second state when avoltage is applied between the first connector and the second connector.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings are incorporated in and constitute a part ofthis specification and, together with the description, explain theadvantages and principles of the invention. In the drawings,

FIGS. 1A-1F illustrate several examples of electrostatic jammingdevices;

FIGS. 2A-2B illustrate examples of jamming sheets;

FIGS. 3A and 3B illustrate some examples of arrangements of jammingsheets in a jamming device;

FIGS. 4A-4F illustrate some examples of jamming sheets having patternsand features;

FIG. 4G illustrates one example of urging elements;

FIG. 5A illustrates one example of a flexible apparatus having a jammingdevice;

FIG. 5B illustrates one example a flexible display having a jammingdevice;

FIG. 6 illustrates a flow diagram of assembling an electrostatic jammingdevice;

FIGS. 7A and 7B illustrate some examples of urging components; and

FIG. 8 illustrates a lab prototype of a jamming device.

In the drawings, like reference numerals indicate like elements. Whilethe above-identified drawings, which may not be drawn to scale, setforth various embodiments of the present disclosure, other embodimentsare also contemplated, as noted in the Detailed Description. In allcases, this disclosure describes the presently disclosed disclosure byway of representation of exemplary embodiments and not by expresslimitations. It should be understood that numerous other modificationsand embodiments can be devised by those skilled in the art, which fallwithin the scope and spirit of this disclosure.

DETAILED DESCRIPTION

Unless otherwise indicated, all numbers expressing feature sizes,amounts, and physical properties used in the specification and claimsare to be understood as being modified in all instances by the term“about.” Accordingly, unless indicated to the contrary, the numericalparameters set forth in the foregoing specification and attached claimsare approximations that can vary depending upon the desired propertiessought to be obtained by those skilled in the art utilizing theteachings disclosed herein. The use of numerical ranges by endpointsincludes all numbers within that range (e.g. 1 to 5 includes 1, 1.5, 2,2.75, 3, 3.80, 4, and 5) and any range within that range.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” encompass embodiments having pluralreferents, unless the content clearly dictates otherwise. As used inthis specification and the appended claims, the term “or” is generallyemployed in its sense including “and/or” unless the content clearlydictates otherwise.

Spatially related terms, including but not limited to, “lower,” “upper,”“beneath,” “below,” “above,” and “on top,” if used herein, are utilizedfor ease of description to describe spatial relationships of anelement(s) to another. Such spatially related terms encompass differentorientations of the device in use or operation in addition to theparticular orientations depicted in the figures and described herein.For example, if an object depicted in the figures is turned over orflipped over, portions previously described as below or beneath otherelements would then be above those other elements.

As used herein, when an element, component or layer for example isdescribed as being “on” “connected to,” “coupled to” or “in contactwith” another element, component or layer, it can be directly on,directly connected to, directly coupled with, in direct contact with, orintervening elements, components or layers may be on, connected, coupledor in contact with the particular element, component or layer, forexample. When an element, component or layer for example is referred toas being “directly on,” “directly connected to,” “directly coupled to,”or “directly in contact with” another element, there are no interveningelements, components or layers for example.

Articles with adjustable stiffness and variable resistance to motion areoften needed. For example, a flexible display is bendable and capable ofsustaining a bent position. At least some embodiments of the presentdisclosure are directed to an electrostatic jamming device thatgenerates a controlled resistance to motion. Such a jamming device canbe incorporated into various devices, systems, and structures to resistdifferent motions, for example, bending motions, translations,rotations, and the like. The motions can be largely planar, or along orwithin surfaces.

Sheets of materials can be jammed together with vacuum to resist motion.Sheets of materials can be jammed together with electrostatics. Thiseliminates the need for a vacuum source and gas impermeable envelope.Previous electrostatic jamming devices had several limitations. Somedevices enable only simple bending of sheets which can only be shapedinto developable surfaces (or a smooth surface with zero Gaussiancurvature). The previous devices tend to be difficult to build andoperate at high voltages.

At least some embodiments of the present disclosure direct to a jammingdevice that can be used to allow bending in one state and resist bendingin another state. In some embodiments, the jamming device includesmultiple sheets and the sheets can be electrostatically jammed to resistmotions. Such jamming device includes conductive layers and dielectriclayers disposed between adjacent conductive layers. At least someembodiments of the present disclosure are directed to electrostaticjamming devices that can operate at low voltages yet achieve usefullevels of motion resistance. Low voltage refers to a voltage that islower than the break down voltage of air for the minimal distancebetween any two oppositely charged conductive layers. Some of theexisting jamming devices include dielectric layers that extend wellbeyond conductive layers to make the shortest path in air between twooppositely charged conductors much longer than the path through thedielectric layer. This makes such jamming devices more difficult tofabricate and susceptible to pin holes or cracks in the dielectriclayers because they would create a distance between oppositely chargedconductors that would allow breakdown of the air (shorting and arcing).Some embodiments of the jamming devices in the present disclosure areimmune to shorting or arcing despite cracks, cuts, pin holes, and otherdefects in the dielectric layers. In some embodiments, the conductivelayers are held at or beyond the thickness of the dielectric layer andthe jamming device is operated below the breakdown voltage of air forthat distance. In some embodiments, jamming sheets can be cut from acontinuous roll of material with no special treatment to the edges ofthe sheets and used to assemble a jamming device. This enables a lowcost high speed manufacturing method for electrostatic sheet jammingdevices where a roll of sheet material is created and then easilyconverted into a desired shape and assembled into a device. In somecases, the low voltage jamming device has the advantage of storing muchless energy in the device and being safer for use on and near the humanbody.

Breakdown voltage refers to the voltage that will cause air to breakdown and become conductive across a gap of a given distance between twoconductors. This is also known as arcing or sparking across the gap. Thebreakdown voltage varies with pressure. The present disclosure generallyrefers to the breakdown voltage of air within the range of standardpressures experienced on earth. In the present disclosure, the breakdownvoltage refers to the shortest distance through air (not through otherdielectric materials) between any two conductors that are notintentionally connected electrically. In the present disclosure, thevalue of the breakdown voltage at a given distance and pressure has beenwell studied for years and is generally accepted to follow Pashen's Lawat gaps above several micrometers but deviate from it at smaller gaps.The breakdown voltage can be determined using a simplified formulaproposed by Babrauskas, Vytenis, Arc Breakdown in Air over Very SmallGap Distances, Interflam 2013, Volume 2, pp. 1489-1498, as provided inEquation (1) below:

$\begin{matrix}{V = \left\{ {\begin{matrix}{{{178} + {2.48d} + {58\sqrt{d}}},\ {d \geq {7\mu m}}} \\{{337},\ {{{3.5}\mu m} \leq d < {7\mu m}}} \\{{97d},\ {d \geq {{3.5}\mu m}}}\end{matrix},} \right.} & (1)\end{matrix}$

where V is the breakdown voltage in Volt, d is the distance between thetwo conductors. Breakdown strength, also referred to as dielectricstrength, can be understood as the maximum electric field strength (V/m)that does not cause breakdown in the material.

Jammed state is used to describe the condition where relative motionsbetween two adjacent parts, sheets, or structures is resisted by theintroduction of an external pressure that squeezes the adjacent parts,sheets, or structures together. The relative motion refers to slidingmotion, rotating motion, or translational motion between two adjacentparts, sheets, or structures in the jamming device. There is a spectrumof “jammed” intensity, which requires different forces to overcome theresistance to motion. The external pressure causing the jamming can comefrom a mechanical source, or application of a vacuum (so atmosphericpressure presses sheets together), from electrostatic attraction betweensheets, or the like. Unjammed state, also referred to as loose state, isused to describe the condition where relative motions between adjacentsheets are not given additional resistance.

FIG. 1A is a cross-section schematic view of a jamming device 100A. Thejamming device 100A includes a first sheet 110, a second sheet 120, anda dielectric layer 130A. The first sheet 110 includes a first conductivelayer 115. The second sheet 120 includes a second conductive layer 125.The dielectric layer 130A is disposed between the first conductive layer115 and the second conductive layer 125. In some implementations, thefirst sheet 100 and the second sheet 120 are non-extensible andflexible. In some cases, the first sheet 100 and the second sheet 120are movable (e.g., slidable, rotatable) relative each other in a loosestate and are not movable with each other in a jammed state, where avoltage (V) is applied to the jamming device 100A. As illustrated, thehigh potential V+ is applied to the first conductive layer 115 and thelow potential V− is applied to the second conductive layer 125. In somecases, the jamming device 100A can be induced to a jammed state with alow voltage.

In some embodiments, the conductive layer (115, 125) can include a metal(e.g., copper, aluminum, steel), which can be annealed or hardened,laminated metal layers or foils (e.g., of the same or different metals);a conductive polymer, or a material filled with conductive particlessuch as carbon. In some embodiments, the sheet (110, 120) can include asupport layer. The support layer can be made from paper or other fibrousmaterial, a polymeric material (e.g., polyurethanes, polyolefins), acomposite material (e.g., carbon fiber), an elastomer (e.g., silicone,styrene-butadiene-styrene), or other materials, and combinationsthereof. In some cases, the support layer has a thickness no less than50 micrometers. In some cases, the support layer has a thickness no lessthan 125 micrometers. In some cases, the support layer and theconductive layer can be combined into one layer. In some cases, thefirst conductive layer 115 is a coating on the first sheet 110. Theconductive coating material may be, for example, copper, aluminum,silver, nickel, indium tin oxide, carbon, graphite, or the like. In someembodiments, the dielectric layer can include silicon oxide, aluminumoxide, titanium oxide, mixed metal oxides, mixed metal nitrides, bariumtitanite, or polymers such as polyimide, acrylates, or the like. In somecases, the dielectric layer can be a dielectric film. In some cases, thedielectric layer 130A is a coating on the first sheet 110. The coatingmaterial can include silicon oxide, aluminum oxide, titanium oxide,mixed metal oxides, mixed metal nitrides, barium titanite, or polymerssuch as polyimide, acrylates, or the like.

In some cases, the dielectric layer 130 is very thin. In some cases, thedielectric layer 130 has a thickness (D) less than or equal to 10micrometers. In some cases, the dielectric layer 130 has a thickness (D)less than or equal to 5 micrometers. In some cases, the dielectric layer130 has a thickness (D) less than or equal to 1 micrometers. In somecases, the distance between the first conductive layer 115 and thesecond conductive layer 125 is no greater than 10 micrometers. In somecases, the jamming device is jammed with a low voltage. In some cases,the low voltage is no greater than 100V. In some cases, such voltage isless than or equal to a break-down voltage of a distance between thefirst and the second conductive layer.

Electrostatic jamming can be understood by modeling each set of adjacentoppositely charged conductive layers with dielectric material betweenthem as a parallel plate capacitor. The opposite charge on those layersare attracted to each other. It can be shown that the attractive forcecreates a compressive pressure on the dielectric material that can berepresented by Equation (2):

$\begin{matrix}{{P = {\frac{ɛ_{r}ɛ_{0}}{2}\frac{V^{2}}{d^{2}}}},} & (2)\end{matrix}$

where ε_(r) is the relative permittivity (or dielectric constant) of thedielectric material, ε₀ is the permittivity of free space (or vacuumpermittivity or electric constant, 8.854187817 . . . ×10⁻¹² F/M), V isthe voltage potential between the two conductive layers, and d is thedistance between the two conductive layers (i.e., the thickness ofdielectric material(s)).

In some cases, the total thickness of the dielectric material includesone or more layers of dielectric material, and may also include some airgap or debris that was trapped between the conductive layers. Whenmultiple dielectric layers exist (including multiple films, coatings,air, debris, etc) they can be modeled in series. In this case each layercan be modeled as a capacitor with capacitance

${C = \frac{ɛ_{r}ɛ_{0}A}{d}},$

where A is the total area, d is the thickness of that layer, and ε_(r)is the relative permittivity of that layer. The total capacitance of thelayers in series can be calculated as

${\frac{1}{C_{tot}} = {\frac{1}{C_{1}} + \frac{1}{C_{2}} + \frac{1}{C_{3}} + \ldots}}\mspace{14mu},$

where C_(tot) is the total capacitance and C₁, C₂ . . . are thecapacitance of the individual layers. The total jamming pressure on thestack of dielectric material can be calculated as Equation (3):

$\begin{matrix}{{P = {\left( \frac{C_{tot}}{A} \right)\frac{V^{2}}{2\left( d_{tot} \right)}}},} & (3)\end{matrix}$

where P is the pressure on the stack of dielectric material, C_(tot) iscalculated above, d_(tot) is the total thickness of the dielectriclayers (i.e., the distance between adjacent two conducting layers). Anaverage relative permittivity for this space between conducting layerscan also be calculated as Equation (4):

$\begin{matrix}{{ɛ_{ave} = \frac{d_{tot}C_{tot}}{Aɛ_{0}}}.} & (4)\end{matrix}$

The electrostatic jamming allows sliding motion, both translational androtational, between oppositely charged conductive layers. The slidinginterface can exist between a conductive layer and a dielectric layer,or between a dielectric layer and another dielectric layer. There may bemore than one slidable interface between two adjacent oppositely chargedconductive layers. When voltage is applied, the pressure created causesthe surfaces of the slidable interface to press against each other andresist motion. The resistance to motion can be modeled by consideringtwo interdigitated sets of sheets being jammed together. The resistanceto sliding two uniform sets of electrostatically jammed sheets apart canbe calculated as Equation (5):

F=PAμN,  (5)

where F is the force required to pull the sets apart (or push themtogether), A is the area of overlap between the sheets (the capacitorarea), μ is the coefficient of friction at the sliding interfaces, and Nis the total number of interfaces. This is a simplified model, since theareas, frictions and material properties may not be constant, but it isuseful to show the primary factors in electrostatic jamming.

It is desireable to have a large jamming pressure that can resistsignificant forces. For many applications, it is desireable to utilize avery low voltage, which increases the safety, and reduces the cost andenergy consumption of the controling electronics. The jammingperformance (i.e., jamming pressure) at very low voltage, according toEquation (2), can be improved by increasing the relative permittivity ofthe dielectric layers, and by reducing the distance between conductivelayers. Using very thin dielectric layers, on the order of a fewmicrometers or less than one micrometer can enable significant jammingpressures at extra low voltage levels. For example, the InternationalElectrotechnical Commision defines an extra low voltage device to be onethat does not exceed 120V d.c. Other standards in the U.K. and USAdefine extra-low voltage systems as not exceeding 75V d.c. or 60V d.c.Based on the calculations earlier, a pressure approximately 10% ofatmospheric pressure can be achieved at 120V if the total thickness ofdielectric layers is around 4.4 micrometers (assuming an averagerelative permittivity of 3). One of the challenges of extra low voltageelectrostatic jamming, is that the jamming pressure is reduced by thesquare of the distance between adjacent oppositely charged conductivelayers. If debris or significant airgaps exist in the slidable interfacebetween the conductive layers, the jamming pressure can become too lowto achieve a usefull resistance to motion, or even to pull the layerstogether. For example, only 1% of atmospheric pressure is achieved at120V if the 4.4 micrometer distance above is increased to around 9.6micrometers by adding a 5.2 micrometer airgap. Therefore, a smalldielectric distance is need for appropriate jamming pressure for ajamming device operating at a low voltage. Additionally, an airgap notonly increases the total dielectric distance, but also reduces theaverage relative permittivity causing an even greater reduction in thejamming pressure, according to the above equations. Some embodiments ofthe present disclosure enable extra low voltage jamming by using verythin dielectric layers and introducing an urging means to bring thesheets together to reduce airgaps.

In some cases, the jamming device 100A includes more than two sheets.The jamming device 100A includes one or more urging elements configuredto keep the first conductive layer and the second conductive layer closeto each other. In some cases, the one or more urging elements is anenclosure that the sheets of the jamming device 100A are disposedwithin. In some cases, the urging elements are spring elements, such asfoam or elastic layers that exert a small pressure on the layers so theymaintain light contact and can then be close enough to be jammedtogether with the application of voltage. In some cases, the gap betweenconductive layers is filled completely with dielectric material and onlya minimal amount of air or other material.

In some cases, the dielectric layer 130A covers less than one hundredpercent (100%) of a circumference of the first sheet 110. In otherwords, the jamming device 100 has the first conductive layer 115 exposedat a portion of or the entire edge of the sheet 100, which is notcovered by dielectric materials at the edge. The exposed conductivelayers can facilitate electrical connections. In some cases, thedielectric layer 130A covers less than eighty percent (80%) of acircumference of the first sheet 110. In some cases, the dielectriclayer 130A covers less than sixty percent (60%) of a circumference ofthe first sheet 110. One challenge for electrostatic jamming devices isprotecting the device from electrical breakdown (or dielectricbreakdown) of air. Some existing electrostatic jamming devices have usedhigh voltages, from several hundred volts to several thousand volts.This requires the jamming device to include continuous dielectric layersthat extended far beyond the conductive layers so that the shortest pathbetween conductive layers in air is many times longer than the pathbetween conductive layers through the dielectric layer. This is becausethe dielectric strength of air at most voltages is only 3 MV/m, whilemany dielectric materials (such as polyethylene or polyimide) havedielectric strengths of 100 or more My/m. Some embodiments of thepresent disclosure, including the one illustrated in FIG. 1A, solvesthat problem by enabling useful jamming pressure with field strengthsbelow the breakdown strength of air. Additional benefit is gained fromthe fact that the actual breakdown strength of air increasessignificantly at small gap distances, particularly below 10 micrometers.By operating below the breakdown voltage of air, some embodiments of thepresent disclosure enable a low cost efficient method of manufacture,where large master rolls of material can be created. Those rolls mightinclude a structural layer, one or more conductive layers, and one ormore dielectric layers. The rolls of material can then be cut into manysmaller sheets of any shape, connected electrically, constrainedmechanically as described later, and assembled into finished products.Because the electrostatic sheet jamming device is operated at a voltageless than the breakdown voltage of air for the thickness of thedielectric material between adjacent oppositely charged conductivelayers, such jamming device is protected from electrical breakdown ofair that can appear as electric arcing (or arc discharge) and causemelting or burning of material. Another advantage of some embodiments ofthe present disclosure is immunity to small pinholes or cuts or otherimperfections in the dielectric layer. At high voltages, even a smallpinhole can cause an electric arc. Some embodiments of the presentdisclosure enables not only the outer perimeter of jamming sheets to becut without an extended dielectric layer, but it also enables complexpatterns to be cut into the jamming sheets that increase theconformability of the sheets and enable other advantages presentedlater.

In some embodiments, the jamming device 110A can include multiplesheets, as the examples illustrated in FIGS. 1B and 1C and described infurther detail below. In some cases, the sheets can be solid orpatterned, e.g., to improve the flexibility (bendability) and/or theextensibility of the sheet. In some embodiments, the sheets havepatterns to increase the flexibility along one or two axes but to have adesired stiffness along a third axis. In some embodiments, the sheetshave patterns cut into them to make them extensible along one or twoaxes or to allow regions of the sheet to move in plane or along asurface relative to other regions. The patterning can be formed by avariety of methods, including but not limited to, steel rule diecutting, extrusion, molding, laser cutting, water jetting, machining,stereolithography or other 3D printing, laser ablation,photolithography, chemical etching, rotary die cutting, stamping, othersuitable negative or positive processing techniques, or combinationsthereof. Solid and patterned sheets of the present disclosure can besingle or multi-layer constructions and can be formed of a variety ofmaterials and layers of materials as described above.

In some embodiments, a jamming device includes two sets of sheets, eachset includes multiple sheets. FIG. 1B illustrates one example of ajamming device 100B having two set of sheets. In the embodimentillustrated, the jamming device 100B includes a first set of sheets 110and a second set of sheets 120, where the first set of sheets and thesecond set of sheets are interdigitated. Each of the first set of sheetsincludes a first conductive layer 115. Each of the second set of sheetsincludes a second conductive layer 125. The jamming device 100B furtherincludes a set of dielectric layers 130B, where an adjacent pair of thefirst conductive layer 115 and the second conductive layer 125 has oneof the set of dielectric layers 130B disposed in between. In someembodiments, the jamming device 100B includes a first connector 140Belectrically conductively coupled to the first conductive layers 115 ofat least part of the first set of sheets 110. In some cases, the jammingdevice 100B includes a second connector 150B electrically conductivelycoupled to the second conductive layers 125 of at least part of thesecond set of sheets 120. In some cases, the first set of sheets 110 andthe second set of sheets 120 are movable relative each other in a loosestate; and the first set of sheets 110 and the second set of sheets 120are jammed with each other in a jammed state. In some cases, the jammedstate is induced when a voltage less than or equal to 100V is appliedbetween the first connector 140B and the second connector 150B, asillustrated. In some cases, the jammed state is induced when a voltageless than or equal to 200V is applied. In some cases, the jammed stateis induced when a voltage less than or equal to a break-down voltage ofair for the distance between adjacent conductive layers of one of thefirst set of sheets and one of the second set of sheets is appliedbetween the first connector 140B and the second connector 150B.

In some embodiments, some dielectric layers 132B, which is a part of thedielectric layers 130, are coated on the first set of sheets. In someembodiments, some dielectric layers 134B, which is a part of thedielectric layers 130, are coated on the second set of sheets. In somecases, each of the dielectric layers is very thin. In some cases, thethickness of each of the dielectric layers is less than or equal to 10micrometers. In some cases, the thickness of each of the dielectriclayers is less than or equal to 5 micrometers. In some cases, thethickness of each of the dielectric layers is less than or equal to 1micrometers. In some cases, a distance between the adjacent pair of thefirst conductive layer and one of the second conductive layer in a loosestate is no greater than 10 micrometers. In some cases, a distancebetween the adjacent pair of the first conductive layer and one of thesecond conductive layer in a loose state is no greater than 10micrometers. In some cases, a distance between the adjacent pair of thefirst conductive layer and one of the second conductive layer in a loosestate is no greater than 5 micrometers.

In some cases, the first set of sheets 110 has a first longitudinal axisand the second set of sheets 120 has a second longitudinal axis, and thefirst longitudinal axis and the second longitudinal axis are parallel toeach other. In some cases, the first longitudinal axis and the secondlongitudinal axis has an angle greater than 0°. In some cases, the firstlongitudinal axis and the second longitudinal axis has an angleproximate to 90°.

The conductive layers and dielectric layers can have variousarrangements. One example arrangement of a jamming device 100C isillustrated in FIG. 1C, where each of the conductive layers issandwiched between two dielectric layers, for example, the conductivelayer 115 is sandwiched between two dielectric layers 132B and theconductive layer 125 is sandwiched between two dielectric layers 134B.In this arrangement, a slidable interface exists between two dielectriclayers in the unjammed state, and the total dielectric thicknessincludes the dielectric layer 132B, the dielectric layer 134B, andpossibly an air gap. Another example arrangement of a jamming device100D is illustrated in FIG. 1D, where each of the conductive layers(115, 125) includes a core layer 160 with a conductive layer on bothsurfaces with a dielectric layer (132B, 134B) external to the conductivelayer. This multiple layered construction can be constructed by stackingor laminating the layers. In some cases, the conductive layers arecoated or deposited (chemical or physical vapor deposition, for example)onto the core layer. In some cases, the core layer 160 providesstructural support. In some cases, the dielectric layers are coated ordeposited (chemical or physical vapor deposition, for example) onto theconductive layers. One other example arrangement of a jamming device100E is illustrated in FIG. 1E, where one of the conductive layers (115,125) by the core layer 160 has an adjacent dielectric layer (132B,134B).

FIG. 1F illustrates one example of a jamming device 100F. The jammingdevice 100F includes jamming sheets (110, 120), each having a core layer160, a conductive layer (115, 125) adjacent to the core layer 160, and adielectric layer (132B, 134B) adjacent to the respective conductivelayer. In some cases, the connector (140B and 150B) provide a mechanicalas well as an electrical connection between the sheets. The connectorcan comprise tape, electrically conductive tape, conductive epoxy,conductive adhesive, conductive paste, elastomeric conductors,conductive or non-conductive thread, staples, clamps, rivets or otherfasteners. The mechanical and electrical connection may be achieved byseparate elements.

In some embodiments, the sheets in the jamming device can be provided ina tape form. In some cases, the tape is in a roll form. FIG. 2Aillustrates one example of a jamming sheet 200 in a continuous tapeform; FIG. 2B illustrates one example of a jamming sheet 220B in a rollform. The jamming sheets (200, 200B) may have any of the configurationsand embodiments as described herein. In one example, the jamming sheet200 has at least a conductive layer and a dielectric layer, for example,illustrated in FIGS. 1B-1E. In some cases, the jamming sheet includes asubstrate or a core layer for support. In some cases, the jamming sheetmay have patterns and features incorporated, for example, as illustratedin FIGS. 4A and 4B, and described in more details below.

In some embodiments, the jamming sheet (200, 200B) can be separated in afirst section 210 and a second section 220. In some embodiments, thejamming sheet 200 includes lines of weakness 240 to allow easyseparation of sections. In some cases, the dielectric layer has athickness less than or equal to 10 micrometers. In some cases, thedielectric layer has a thickness less than or equal to 5 micrometers. Insome cases, the dielectric layer has a thickness less than or equal to 1micrometer. In some cases, the sheet (200, 200B) is non-extensible andflexible. In some embodiments, the first and second sections are removedfrom the jamming sheet 200B by die cutting, laser cutting, rotary diecutting, or other suitable techniques.

In some embodiments, a jamming device can be formed by the first section210 of the sheet and the second section of the sheet 220. In someembodiments, the first section and the second section are movablerelative each other in the loose state and are jammed with each other inthe jammed state. In some cases, the jammed state is induced when avoltage is applied between the conductive layer of the first section andthe conductive layer of the second section. In some cases, the appliedvoltage is less than or equal to a break-down voltage of a distancebetween the first and the second conductive layer. In some cases, theapplied voltage is no greater than 100V. In some cases, the appliedvoltage is no greater than 200V. In some cases, the distance between theconductive layer of the first section and the conductive layer of thesecond section is no greater than 5 micrometers. In some cases, thedistance between the conductive layer of the first section and theconductive layer of the second section is no greater than 10micrometers. In some embodiments, the dielectric layer is a coating onthe sheet 200. In some embodiments, the conductive layer is a coating onthe sheet 200.

In some embodiments, the sheets are in various arrangements in a jammingdevice to achieve the desired functionality. In some cases, the sheetshave a connector at one end, as illustrated in FIGS. 1B and 1C. FIGS. 3Aand 3B illustrate some other examples of arrangements of jamming sheetsin a jamming device. FIG. 3A illustrate two sets of jamming sheets (310,320) arranged at an angle in a jamming device 300A. Each jamming sheetcan have any of the configurations and embodiments as described herein.In some embodiments, each of the first set of jamming sheets 310 and thesecond set of jamming sheets 320 has a conductive layer. In someembodiments, each of the first set of jamming sheets 310 and the secondset of jamming sheets 320 has a conductive layer and a dielectric layer.In some cases, the first set of jamming sheets 310 and the second set ofjamming sheets 320 are interdigitated. In some cases, the jamming sheetsare arranged such that a dielectric layer is disposed between twoadjacent conductive layers. In some cases, the first set of jammingsheets 310 has connectors 330 on two edges, respectively 331A and 332A.In the example illustrated, the connectors 330 are at the two opposingedges. In some cases, the second set of jamming sheets 320 hasconnectors 340 on two edges, respectively 341A and 342A. In the exampleillustrated, the connectors 341A and 342A are disposed proximate to twoopposing edges. In some cases, the connectors 330 and 340 areelectrically coupled to the conductive layers of some or all of thejamming sheets (310, 320). In some cases, one of the two connectors(331A, 332A) is electrically coupled to the conductive layers of some orall of the jamming sheets 310. In some cases, one of the two connectors(341A, 342A) is electrically coupled to the conductive layers of some orall of the jamming sheets 320.

The first set of jamming sheets 310 has a longitudinal axis X and thesecond set of jamming sheets 320 has a longitudinal axis Y. In somecases, the axis X and the axis Y form a degree greater than 0° and lessthan 180°. In one embodiment, the axis X and the axis Y form a degreeclose to 90°. In one embodiment, the axis X and the axis Y form a degreeabout 45°. In one embodiment, the axis X and the axis Y form a degreeabout 130°. In one embodiment as illustrated, the connectors (330, 340)are connecting the shorter edges of the sheets. In some embodiments, theconnectors are connecting the longer edges of the sheets.

In some embodiments, the first set of sheets 310 and the second set ofsheets 320 are movable relative to each other in a loose state andjammed with each other in a jammed state. In some cases, the first setof sheets 310 and/or the second set of sheets 320 can be rotated in theloose state. In some cases, the jammed state is induced when a voltageis applied between the first connector and the second connector. In somecases, the applied voltage is no greater than 100V. In some cases, theapplied voltage is no greater than 200V. In some cases, the appliedvoltage is less than or equal to a break-down voltage of a distancebetween the first and the second conductive layer. In some cases, adistance between the adjacent conductive layers in a loose state is nogreater than 10 micrometers. In some cases, a distance between theadjacent conductive layers in a loose state is no greater than 5micrometers.

In the embodiment illustrated in FIG. 3A, the jamming device 300Aincludes enclosures 335 and 345. In some embodiments, the enclosures 335and 345 include the connectors 330 and 340. In some embodiments, theenclosures 335 and 345 are partially opened. In some embodiments, theenclosures 335 and 345 are configured to keep the jamming sheets 310 and320 disposed close to each other. In some embodiments, the enclosures(335 and/or 345) are flexible. The enclosures 335 and 345 are examplesof a means of urging the sheets into close proximity.

FIG. 3B illustrates another example of a jamming device 310B having twosets of jamming sheets (310, 320). Each jamming sheet can have any ofthe configurations and embodiments as described herein. In someembodiments, each of the first set of jamming sheets 310 and the secondset of jamming sheets 320 has a conductive layer. In some embodiments,each of the first set of jamming sheets 310 and the second set ofjamming sheets 320 has a conductive layer and a dielectric layer. Insome cases, the first set of jamming sheets 310 and the second set ofjamming sheets 320 are interdigitated. In some cases, the jamming sheetsare arranged such that a dielectric layer is disposed between twoadjacent conductive layers. In some cases, the first set of jammingsheets 310 has connectors proximate to two edges, respectively 331B and332B. In the example illustrated, the connectors 331B and 332B aredisposed proximate to two adjacent edges. In some cases, the second setof jamming sheets 320 has connectors 340 on two edges, respectively 341Band 342B. In the example illustrated, the connectors 341B and 342B aredisposed proximate to two adjacent edges. In some cases, the connectors(331B, 332B, 341B, 342B) are electrically coupled to the conductivelayers of some or all of the jamming sheets (310, 320). In some cases,one of the two connectors (331B, 332B) is electrically coupled to theconductive layers of some or all of the jamming sheets 310. In somecases, one of the two connectors (341B, 342B) is electrically coupled tothe conductive layers of some or all of the jamming sheets 320. Theconnectors 331B, 332B, 341B, 342B can also comprise a means of urgingthe sheets to stay within close proximity of each other.

In some embodiments, the first set of sheets 310 and the second set ofsheets 320 are movable relative to each other in a loose state andjammed with each other in a jammed state. In the example illustrated,the first set of sheets 310 and/or the second set of sheets 320 can berotated or translated according to the arrows. In some cases, the jammedstate is induced when a voltage is applied between the first connectorand the second connector. In some cases, the applied voltage is nogreater than 100V. In some cases, the applied voltage is no greater than200V. In some cases, the applied voltage is less than or equal to abreak-down voltage of a distance between the first and the secondconductive layer. In some cases, a distance between the adjacentconductive layers in a loose state is no greater than 10 micrometers. Insome cases, a distance between the adjacent conductive layers in a loosestate is no greater than 5 micrometers.

In some embodiments, the sheets used in a jamming device may be a solidflat sheet. In some embodiments, the sheets used in a jamming device maybe sheets having patterns, protrusions, slits, openings, and otherfeatures. In some embodiments, the sheets may include three dimensionalstructures but the sheets are generally flat. FIGS. 4A and 4B illustratesome examples of sheets having patterns and features. FIG. 4Aillustrates a jamming sheet 400A having patterns. In some cases, thejamming sheet 400A is made of non-extensible materials. In some cases,the jamming sheet 400A includes a set of slit features 410A such thatthe sheet is extensible on an axis X. In some cases, the jamming sheet400A includes a set of slit features 410A such that the sheet isextensible on an axis Y. In some cases, the jamming sheet 400A includesa conductive layer. In some cases, the jamming sheet 400A includes botha conductive layer and a dielectric layer.

FIG. 4B illustrates one other example of a jamming sheet 400B havingpatterns that can be used in a jamming device. In some cases, thepattern includes a set of slit features 410B that allow the sheet to beextensible in one axis, along axis Y for instance. In some cases, thisextensibility gives the sheet increased conformability to bend out ofplane along a path in that axis. For example, because of theextensibility along axis Y, the sheet in FIG. 4B could be more easilyrolled into a cylinder whose axis is aligned along axis X than a sheetwithout the slits.

FIG. 4C illustrates a cross-sectional view of another example of jammingdevice 400C using jamming sheets 410C and 420C; and FIG. 4D illustratesthe jamming sheets 410C and 420C when they are apart from each other. Insome cases, the jamming sheet 410C includes a substrate 412C. In somecases, the substrate 412C has a general plane 415C. In some cases, thejamming sheet 410C includes a set of features 414C protruded from thesubstrate 412C. Similarly, the jamming sheet 420C may include asubstrate 422C, and a set of features 424C protruded from the substrate424C. In some cases, a jamming device may be formed by two or morejamming sheets 410C. In some cases, the set of features 414C and the setof features 424C are configured to mate with each other. In some cases,the jamming sheets 410C and 420C are non-extensible and flexible. Insome cases, the jamming sheets 410C and/or 420C include a conductivelayer. In some cases, the jamming sheets 410C and/or 420C include both aconductive layer and a dielectric layer.

In some cases, the set of features 414C and 424C have dimensions thatare a few millimeters in length. In some cases, the features havedimensions that are less than one millimeter in length. In some cases,the features are a few micrometers to 50 micrometers in length. Theheight (H) of the set of features 414C refers to an average height ofthe set of features 414C from the general plane 415C. In some cases, theheight of the set of features 414C is equal to or less than 10millimeters. In some cases, the height of the set of features 414C isequal to or less than 1 millimeters. In some cases, the height of theset of features 414C is equal to or less than 50 micrometers. In somecases, each of the set of features is a prism, a pyramid, a rectangularprotrusion, an ellipsoidal protrusion, a sawtooth, or a sinusoidprotrusion. In some cases, the features do not change along one axis, asif they were extruded. In some cases, the features change along morethan one axis, comprising discrete three-dimensional features. In somecases, the features repeat in patterns and in some cases, they arerandom. For example, random features with dimensions of a few microns orless can provide a desired coefficient of friction and can also providesome resistance to small debris particles.

In some embodiments, the jamming sheet 410C and the jamming sheet 420Care movable relative to each other in a loose state and jammed with eachother in a jammed state. In some cases, the jammed state is induced whena voltage is applied to sheets. In some cases, the applied voltage is nogreater than 500V. In some cases, the applied voltage is no greater than50V. In some cases, the applied voltage is no greater than 100V. In somecases, the applied voltage is no greater than 200V. In some cases, thedistance between adjacent conductive layers in the loose state isrelatively large, allowing freedom of motion of the two sheets. Thesheets can be attached to separate articles (462D and 464D) as shown inFIG. 4D. When the articles are brought together and the jamming sheetsare placed in close proximity and a voltage applied to induce the jammedstate, then the articles will resist moving apart. In some cases, theapplied voltage is less than or equal to a break-down voltage of adistance between the conductive layers on the sheets. In some cases, adistance between the adjacent conductive layers in a loose state is nogreater than 10 micrometers. In some cases, a distance between theadjacent conductive layers in a loose state is no greater than 5micrometers. In some cases, some of the first features are mated withsome of the second features in the jammed state. Mating of the featurescan create a significant increase in the resistance of the sheets tomotion caused by shear forces. In some cases, the features are designedto increase the resistive force in specific directions.

FIG. 4E illustrates a cross-sectional view of one example of jammingdevice 400E using jamming sheets 410E and 420E. In some cases, thejamming sheet 410E includes a substrate and a set of features 414Eprotruded from the substrate 412E. Similarly, the jamming sheet 420E mayinclude a substrate and a set of features 424E protruded from thesubstrate. In some cases, a jamming device may be formed by two or morejamming sheets. In the example illustrated, the features (414E, 424E)are cylindrical or rectangular protrusions. In some cases, the set offeatures 414E and the set of features 424E are configured to mate witheach other. In some cases, the jamming sheets 410E and 420E arenon-extensible and flexible. In some cases, the jamming sheets 410Eand/or 420E include a conductive layer. In some cases, the jammingsheets 410E and/or 420E include both a conductive layer and a dielectriclayer.

FIG. 4F illustrates a cross-sectional view of one example of jammingdevice 400F using jamming sheets 410F and 420F. In some cases, thejamming sheet 410F includes a substrate and a set of features 414Fprotruded from the substrate 412F. Similarly, the jamming sheet 420F mayinclude a substrate and a set of features 424F protruded from thesubstrate. In some cases, a jamming device may be formed by two or morejamming sheets. In the example illustrated, the features (414F, 424F)are sinusoidal protrusions. In some cases, the set of features 414F andthe set of features 424F are configured to mate with each other. In somecases, the jamming sheets 410F and 420F are non-extensible and flexible.In some cases, the jamming sheets 410F and/or 420F include a conductivelayer. In some cases, the jamming sheets 410F and/or 420F include both aconductive layer and a dielectric layer.

In some embodiments, the jamming device includes urging elements thaturge the sets of sheets to remain close to one another in the loose,unjammed state. One example of urging elements is shown in FIG. 4G,where the urging elements include a highly compliant outer layer 452. Insome cases, the urging elements include a highly compliant inner layer450. In some cases, the urging elements is made of a stretchablematerial, for example spandex, or some elastic material. In some cases,the jamming sheets 400G are contained between the urging elements. Insome cases, the jamming sheets 400G have patterns that allow them to beextensible in any axis such that they can conform to a complex surface,such as the human joint shown.

The jamming device may be used in various flexible apparatus andequipment to allow the apparatus/equipment to hold a bent position. FIG.5A illustrates one example of a flexible apparatus 500A having aflexible component layer 510 and a jamming device 520. The flexiblecomponent layer 510 includes at least one component. The jamming device520 may have any of the configurations and embodiments of a jammingdevice as described herein. In some cases, the jamming device 520 isdisposed proximate to the flexible component layer 510. In some cases,the jamming device has a loose state and a jammed state, where thejamming device permits the flexible component layer to be bent in theloose state, and the jamming device is configured to resist bending ofthe flexible component layer in the jammed state.

FIG. 5B illustrates one example of a display 500B using a jamming device520B. In this example, the flexible component layer 510 is a flexible(or bendable) display, or referred to as a flexible display panel. Thejamming device 520B may have any one of the embodiments andconfigurations of a jamming device as described herein. In some cases,the display panel 500B includes two rigid members 530B. As an example,the rigid member may also be a part of the heat sink, battery,electromagnetic shielding, or other components for the display panel500B. The jamming device 520B is disposed proximate to the flexiblecomponent layer 510B. In some embodiments, the jamming device covers amajority of the surface of the flexible component layer. In some cases,the jamming device can include one or more jamming elements disposedproximate to the flexible component layer, where each jamming elementmay have any of the configurations and embodiments of a jamming deviceas described herein.

FIG. 6 illustrates one example of flow diagram of assembling anelectrostatic jamming device. One or more steps are optional. First,retrieve a roll of electrostatic jamming material (step 610). Separateinto individual jamming sheets from the roll (step 620). The individualsheets can be separated by die cutting, laser cutting, rotary diecutting, or other suitable techniques. Stack individual sheets into twoor more sets (step 630). Connect each set of sheets electrically (step640). Assemble the two or more sets of jamming sheets into a jammingdevice (step 650). In some cases, the two or more sets of sheets arearranged to be interdigitated.

FIGS. 7A and 7B illustrate some examples of urging components, which canbe used in a jamming device. FIG. 7A illustrates one example of anurging component 720A. As illustrated, the urging component is anenclosure with fixed clearance. In this example, the urging componentdoes not add pressure to the jamming sheets 710. The jamming sheets canuse any configurations and embodiments as illustrated and providedherein. FIG. 7B illustrates another example of an urging component 720B.As illustrated, the urging component 720B is a rivet style enclosurewith fixed clearance. In this example, the urging component does not addpressure to the jamming sheets 710. In some embodiments, a compliantlayer (such as a foam or spring) could be added into the clearance areato apply some small pressure on the sheets to urge them together.

EXEMPLARY EMBODIMENTS

Embodiment A1. An electrostatic sheet jamming device comprising a firstsheet having a first conductive layer, a first dielectric layer disposedadjacent to the first conductive layer, a second sheet comprising asecond conductive layer and disposed proximate to the first dielectriclayer. The first dielectric layer is disposed between the firstconductive layer and the second conductive layer. The first dielectriclayer has a thickness less than or equal to 10 micrometers. The firstsheet and the second sheet are non-extensible and flexible, wherein thefirst sheet and the second sheet are slidable relative to each other ina first state. The first sheet and the second sheet are jammed with eachother in a second state when a voltage is applied between the firstconductive layer and the second conductive layer. The applied voltage isless than or equal to a break-down voltage of air at a distance betweenthe first conductive layer and the second conductive layer.

Embodiment A2. The jamming device of Embodiment A1, wherein the firstdielectric layer is a coating on the first sheet.

Embodiment A3. The jamming device of Embodiment A1 or A2, furthercomprising a second dielectric layer, wherein the second sheet has afirst surface and a second surface opposing the first surface, whereinthe second conductive layer is on the first surface of the second sheet,and wherein the second dielectric layer is disposed proximate closer tothe second surface of the second sheet than the first surface of thesecond sheet.

Embodiment A4. The jamming device of any one of Embodiments A1-A3,further comprising: a second dielectric layer disposed proximate to thesecond sheet.

Embodiment A5. The jamming device of any one of Embodiments A1-A4,wherein the second dielectric layer is coated on the second sheet.

Embodiment A6. The jamming device of any one of Embodiments A1-A5,wherein the applied voltage is no greater than 100V.

Embodiment A7. The jamming device of any one of Embodiments A1-A6,wherein the distance between the first conductive layer and the secondconductive layer in the first state is no greater than 10 micrometers.

Embodiment A8. The jamming device of any one of Embodiments A1-A7,further comprising: one or more urging elements configured to keep thefirst conductive layer and the second conductive layer close to eachother.

Embodiment A9. The jamming device of Embodiment A8, wherein the one ormore urging elements comprise at least one of a highly compliant outerlayer, a highly compliant inner layer, a fixed clearance limitingelement, and a spring element.

Embodiment A10. The jamming device of any one of Embodiments A1-A9,wherein the first dielectric layer covers less than one hundred percentof a circumference of the first sheet.

Embodiment A11. The jamming device of any one of Embodiments A1-A10,wherein the first dielectric layer has a thickness less than or equal to5 micrometers.

Embodiment A12. The jamming device of any one of Embodiments A1-A11,wherein a direct path between the first conductive layer and the secondconductive layer for at least one part of the jamming device isapproximately the same length as the distance between the first andsecond conductive layers in the second state.

Embodiment A13. The jamming device of any one of Embodiments A1-A12,wherein the first sheet is separated from a large sheet having aconductive layer.

Embodiment A14. The jamming device of Embodiment A13, wherein the largesheet is a roll of sheet.

Embodiment A15. The jamming device of any one of Embodiments A1-A14,wherein the first sheet is patterned such that it is extensible in atleast one axis.

Embodiment A16. The jamming device of any one of Embodiments A1-A15,wherein the first sheet has patterned openings such that it isextensible in at least one axis.

Embodiment A17. The jamming device of any one of Embodiments A1-A16,wherein the first sheet has a plurality of protruded features.

Embodiment A18. The jamming device of Embodiment A17, wherein the secondsheet has a plurality of protruded features.

Embodiment A19. The jamming device of Embodiment A18, wherein at leastsome of the plurality of protruded features of the first sheet are matedwith some of the plurality of protruded features of the second sheet inthe second state.

Embodiment A20. The jamming device of any one of Embodiments A1-A19,wherein the first dielectric layer has a relative permittivity greaterthan 3.

Embodiment A21. The jamming device of any one of Embodiments A1-A20,wherein the first dielectric layer comprises an inorganic compound.

Embodiment A22. The jamming device of any one of Embodiments A1-A21,wherein a coefficient of friction of the first sheet is less than 0.4.

Embodiment A23. The jamming device of any one of Embodiments A1-A22,wherein the first sheet comprises a core layer providing structuralsupport.

Embodiment B1. An electrostatic sheet jamming device comprising a firstset of sheets, each of the first set of sheets comprising a firstconductive layer, a second set of sheets, each of the second set ofsheets comprising a second conductive layer, a set of dielectric layers,a first connector electrically conductively connected to firstconductive layers of at least part of the first set of sheets, and asecond connector electrically conductively connected to secondconductive layers of at least part of the second set of sheets. Thefirst set of sheets and the second set of sheets are interdigitated.Each of the adjacent pair of the first set of sheets and the second setof sheets has one of the set of dielectric layers disposed in between.Each of the set of dielectric layers has a thickness less than or equalto 10 micrometers. The first set of sheets and the second set of sheetsare slidable relative to each other in a first state. The first set ofsheets and the second set of sheets are jammed with each other in asecond state when a voltage is applied between the first connector andthe second connector, where the applied voltage is less than or equal toa break-down voltage of air at a distance between adjacent conductivelayers of one of the first set of sheets and one of the second set ofsheets.

Embodiment B2. The jamming device of Embodiment B1, wherein at leastsome of the set of dielectric layers are coated on the first set ofsheets.

Embodiment B3. The jamming device of Embodiment B2, wherein at leastsome of the set of dielectric layers are coated on the second set ofsheets.

Embodiment B4. The jamming device of any one of Embodiments B1-B3,wherein the first set of sheets has a first longitudinal axis and thesecond set of sheets has a second longitudinal axis, and wherein thefirst longitudinal axis and the second longitudinal axis are generallyparallel to each other.

Embodiment B5. The jamming device of any one of Embodiments B1-B4,wherein a distance between an adjacent pair of the first conductivelayer and the second conductive layer in the first state is no greaterthan 10 micrometers.

Embodiment B6. The jamming device of any one of Embodiments B1-B5,wherein the first dielectric layer covers less than one hundred percentof a circumference of the first sheet.

Embodiment B7. The jamming device of any one of Embodiments B1-B6,wherein the applied voltage is no greater than 100V.

Embodiment B8. The jamming device of any one of Embodiments B1-B7,further comprising: one or more urging elements configured to keep thefirst set of sheets and the second set of sheets close to each other.

Embodiment B9. The jamming device of Embodiment B8, wherein the one ormore urging elements comprise at least one of a highly compliant outerlayer, a highly compliant inner layer, a fixed clearance limitingelement, and a spring element.

Embodiment B10. The jamming device of any one of Embodiments B1-B9,wherein the first dielectric layer covers less than one hundred percentof a circumference of the corresponding sheet.

Embodiment B11. The jamming device of any one of Embodiments B1-B10,wherein at least one of the set of dielectric layers has a thicknessless than or equal to 5 micrometers.

Embodiment B12. The jamming device of any one of Embodiments B1-B11,wherein the first set of sheets are separated from a large sheet havinga conductive layer.

Embodiment B13. The jamming device of Embodiment B12, wherein the largesheet is a roll of sheet.

Embodiment B14. The jamming device of any one of Embodiments B1-B13,wherein at least one of the first set of sheets is patterned such thatit is extensible in at least one axis.

Embodiment B15. The jamming device of any one of Embodiments B1-B14,wherein at least one of the first set of sheets has patterned openingssuch that it is extensible in at least one axis.

Embodiment B16. The jamming device of any one of Embodiments B1-B15,wherein at least one of the first set of sheets has a plurality ofprotruded features.

Embodiment B17. The jamming device of Embodiment B16, wherein at leastone of the first set of sheets has a plurality of protruded features.

Embodiment B18. The jamming device of Embodiment B17, wherein at leastsome of the plurality of protruded features of at least one of the firstset of sheets are mated with some of the plurality of protruded featuresof at least one of the second set of sheets in the second state.

Embodiment B19. The jamming device of any one of Embodiments B1-B18,wherein at least one of the set of dielectric layers has a relativepermittivity greater than 3.

Embodiment B20. The jamming device of any one of Embodiments B1-B19,wherein at least one of the set of dielectric layers comprises aninorganic compound.

Embodiment B21. The jamming device of any one of Embodiments B1-B20,wherein a coefficient of friction of at least one of the first set ofsheets is less than 0.4.

Embodiment B22. The jamming device of any one of Embodiments B1-B21,wherein at least one of the first set of sheets comprises a core layerproviding structural support.

Embodiment C1. An electrostatic sheet jamming device formed by a sheethaving a conductive layer and a dielectric layer. The jamming deviceincludes a first section of the sheet, the first section being separatedfrom the sheet, and a second section of the sheet, the second sectionbeing separated from the sheet. The sheet is non-extensible andflexible. The first section and the second section are slidable relativeto each other in a first state. The first section and the second sectionare jammed with each other in a second state when a voltage is appliedbetween a conductive layer of the first section and a conductive layerof the second section.

Embodiment C2. The jamming device of Embodiment C1, wherein the appliedvoltage is less than or equal to a break-down voltage of air at adistance between the first and the second conductive layer.

Embodiment C3. The jamming device of Embodiment C1 or Embodiment C2,wherein the applied voltage is no greater than 100V.

Embodiment C4. The jamming device of any one of Embodiments C1-C3,wherein a distance between the first section and the second section isno greater than 10 micrometers in the first state.

Embodiment C5. The jamming device of any one of Embodiments C1-C4,further comprising: one or more urging elements configured to keep thefirst section and the second section close to each other.

Embodiment C6. The jamming device of Embodiment C5, wherein the one ormore urging elements comprise at least one of a highly compliant outerlayer, a highly compliant inner layer, a fixed clearance limitingelement, and a spring element.

Embodiment C7. The jamming device of any one of Embodiments C1-C6,wherein the sheet is packaged in a roll.

Embodiment C8. The jamming device of any one of Embodiments C1-C7,wherein the sheet comprises a line of weakness between adjacentsections.

Embodiment C9. The jamming device of any one of Embodiments C1-C8,wherein a coefficient of friction of the sheet is less than 0.4.

Embodiment C10. The jamming device of any one of Embodiments C1-C9,wherein a dielectric layer of the first section covers less than onehundred percent of a circumference of the first section.

Embodiment C11. The jamming device of any one of Embodiments C1-C10,wherein the dielectric layer has a thickness less than or equal to 5micrometers.

Embodiment C12. The jamming device of any one of Embodiments C1-C11,wherein a direct path between the first conductive layer and the secondconductive layer for at least one part of the jamming device isapproximately the same length as the distance between the first andsecond conductive layers in the second state.

Embodiment C13. The jamming device of any one of Embodiments C1-C12,wherein the first sheet is separated from a large sheet having aconductive layer.

Embodiment C14. The jamming device of Embodiment C13, wherein the largesheet is a roll of sheet.

Embodiment C15. The jamming device of any one of Embodiments C1-C14,wherein the first sheet is patterned such that it is extensible in atleast one axis.

Embodiment C16. The jamming device of any one of Embodiments C1-C15,wherein the first section has patterned openings such that it isextensible in at least one axis.

Embodiment C17. The jamming device of any one of Embodiments C1-C16,wherein the first section has a plurality of protruded features.

Embodiment C18. The jamming device of Embodiment C17, wherein the secondsection has a plurality of protruded features.

Embodiment C19. The jamming device of Embodiment C18, wherein at leastsome of the plurality of protruded features of the first section aremated with some of the plurality of protruded features of the secondsection in the second state.

Embodiment C20. The jamming device of any one of Embodiments C1-C19,wherein the dielectric layer has a relative permittivity greater than 3.

Embodiment C21. The jamming device of any one of Embodiments C1-C20,wherein the dielectric layer comprises an inorganic compound.

Embodiment C22. The jamming device of any one of Embodiments C1-C21,wherein the sheet comprises a core layer providing structural support.

Embodiment C23. The jamming device of any one of Embodiments C1-C22,wherein the dielectric layer has a thickness less than or equal to 10micrometers.

Embodiment C24. The jamming device of any one of Embodiments C1-C23,wherein the dielectric layer is a coating on the sheet.

Embodiment D1. A method including the steps of: retrieving a sheethaving a conductive layer and a dielectric layer; separating a first setof sections from the sheet; connecting the first set of sectionselectrically via a first connector; separating a second set of sectionsfrom the sheet; connecting the second set of sections electrically via asecond connector; and assembling the first set of sections and thesecond set of sections into a jamming device. The sheet isnon-extensible and flexible. The first set of sections and the secondset of sections are slidable relative to each adjacent pair in a firststate. The first set of sections and the second set of sections arejammed together in a second state when a voltage is applied between thefirst connector and the second connector.

Embodiment D2. The method of Embodiment D1, wherein the dielectric layeris a coating on the sheet.

Embodiment D3. The method of Embodiment D1 or D2, wherein the dielectriclayer has a thickness less than or equal to 10 micrometers.

Embodiment D4. The method of any one of Embodiments D1-D3, wherein thedielectric layer has a thickness less than or equal to 5 micrometers.

Embodiment D5. The method of any one of Embodiments D1-D4, furthercomprising: assembling the first set of sections and the second set ofsections with one or more urging elements.

Embodiment D6. The method of Embodiment D5, wherein the one or moreurging elements comprise at least one of a highly compliant outer layer,a highly compliant inner layer, a fixed clearance limiting element, anda spring element.

Embodiment D7. The method of any one of Embodiments D1-D6, wherein thesheet is packaged in a roll.

Embodiment D8. The method of any one of Embodiments D1-D7, wherein thesheet comprises a line of weakness between adjacent sections.

Embodiment D9. The method of any one of Embodiments D1-D8, wherein acoefficient of friction of the sheet is less than 0.4.

Embodiment D10. The method of any one of Embodiments D1-D9, wherein thedielectric layer of at least one of the first set of sections coversless than one hundred percent of a circumference of the at least one ofthe first set of sections.

Embodiment D11. The method of any one of Embodiments D1-D10, wherein adistance between an adjacent one of the first set of sections and one ofthe second set of sections is no greater than 10 micrometers in thefirst state.

Embodiment D12. The method of any one of Embodiments D1-D11, wherein adirect path between two conductive layers of the adjacent one of thefirst set of sections and one of the second set of sections isapproximately the same length as the distance between the two conductivelayers in the second state.

Embodiment D13. The method of any one of Embodiments D1-D12, wherein thesheet is patterned such that it is extensible along at least one axis.

Embodiment D14. The method of any one of Embodiments D1-D13, wherein thesheet has patterned openings such that it is extensible along at leastone axis.

Embodiment D15. The method of any one of Embodiments D1-D14, wherein thesheet has a plurality of protruded features.

Embodiment D16. The method of Embodiment D15, wherein at least some ofthe plurality of protruded features of at least one of the first set ofsections are mated with some of the plurality of protruded features ofat least one of the second set of sections in the second state.

Embodiment D17. The method of any one of Embodiments D1-D16, wherein thedielectric layer has a relative permittivity greater than 3.

Embodiment D18. The method of any one of Embodiments D1-D17, wherein thedielectric layer comprises an inorganic compound.

Embodiment D19. The method of any one of Embodiments D1-D18, wherein thesheet comprises a core layer providing structural support.

Embodiment D20. The method of any one of Embodiments D1-D19, wherein theapplied voltage is less than or equal to a break-down voltage of air ata distance between the first and the second conductive layer.

Embodiment D21. The method of any one of Embodiments D1-D20, wherein theapplied voltage is no greater than 100V.

Embodiment E1. An electrostatic sheet jamming apparatus comprising afirst sheet comprising a first conductive layer, the first sheetcomprising a set of first features protruded from a first general planeof the first sheet, a first dielectric layer disposed adjacent to thefirst conductive layer, and a second sheet comprising a secondconductive layer and disposed proximate to the first dielectric layer,the second sheet comprising a set of second features protruded from asecond general plane of the second sheet. The first dielectric layer isdisposed between the first conductive layer and the second conductivelayer. The first sheet and the second sheet are non-extensible andflexible, wherein at least some of the set of first features areconfigured to mate with at least some of the set of second features. Thefirst sheet and the second sheet are movable relative each other in afirst state. The first sheet and the second sheet are jammed with eachother in a second state when a voltage is applied between the firstconductive layer and the second conductive layer.

Embodiment E2. The apparatus of Embodiment E1, wherein the set of firstfeatures has a first height representing an average height of the set offirst features from the first general plane.

Embodiment E3. The apparatus of Embodiment E2, wherein the first heightis equal to or less than 10 millimeters.

Embodiment E4. The apparatus of Embodiment E2, wherein the first heightis equal to or less than 1 millimeters.

Embodiment E5. The apparatus of Embodiment E2, wherein the set of secondfeatures has a second height representing an average height of the setof second features from the second general plane.

Embodiment E6. The apparatus of Embodiment E5, wherein the second heightis equal to or less than 10 millimeters.

Embodiment E7. The apparatus of Embodiment E5, wherein the second heightis equal to or less than 1 millimeters.

Embodiment E8. The apparatus of any one of Embodiments E1-E7, whereinone of the set of first features is a prism, a pyramid, a rectangularprotrusion, an ellipsoidal protrusion, a sawtooth, or a sinusoid.

Embodiment E9. The apparatus of any one of Embodiments E1-E8, whereinthe first conductive layer is a coating on the first sheet.

Embodiment E10. The apparatus of any one of Embodiments E1-E9, whereinthe first dielectric layer is a coating on the first sheet.

Embodiment E11. The apparatus of Embodiment E10, further comprising: asecond dielectric layer coated on the second sheet.

Embodiment E12. The apparatus of Embodiment E11, wherein the seconddielectric layer has a thickness less than or equal to 5 micrometers.

Embodiment E13. The apparatus of any one of Embodiments E1-E12, whereinat least some of the set of first features have a same first shape.

Embodiment E14. The apparatus of Embodiment E13, wherein at least someof the set of first features have a same second shape.

Embodiment E15. The apparatus of Embodiment E14, wherein the first shapeis a same shape as the second shape.

Embodiment E16. The apparatus of any one of Embodiments E1-E15, whereinsome of the set of first features are mated with some of the set ofsecond features in the second state.

Embodiment E17. The apparatus of Embodiment E16, wherein the some of theset of first features are in contact with the some of the set of secondfeatures.

Embodiment E18. The apparatus of any one of Embodiments E1-E17, whereinthe applied voltage is no greater than a break-down voltage of adistance between the first and the second conductive layer.

Embodiment E19. The apparatus of any one of Embodiments E1-E18, whereinthe applied voltage is no greater than 100V.

Embodiment E20. The apparatus of any one of Embodiments E1-E19, furthercomprising: one or more urging elements configured to keep the firstsheet and the second sheet close to each other.

Embodiment E21. The apparatus of Embodiment E20, wherein the one or moreurging elements comprise at least one of a highly compliant outer layer,a highly compliant inner layer, a fixed clearance limiting element, anda spring element.

Embodiment E22. The apparatus of any one of Embodiments E1-E21, whereinthe first dielectric layer has a thickness less than or equal to 10micrometers.

Embodiment E23. The apparatus of any one of Embodiments E1-E22, whereinthe first dielectric layer has a thickness less than or equal to 5micrometers.

Embodiment E24. The apparatus of any one of Embodiments E1-E23, whereinthe first sheet is separated from a large sheet having a conductivelayer.

Embodiment E25. The apparatus of Embodiment E24, wherein the large sheetis a roll of sheet.

Embodiment E26. The apparatus of any one of Embodiments E1-E25, whereinthe first sheet is patterned such that it is extensible in at least oneaxis.

Embodiment E27. The apparatus of any one of Embodiments E1-E26, whereinthe first dielectric layer has a relative permittivity greater than 3.

Embodiment E28. The apparatus of any one of Embodiments E1-E27, whereinthe first dielectric layer comprises an inorganic compound.

Embodiment E29. The apparatus of any one of Embodiments E1-E28, whereinat least one of the first sheet and the second sheet comprises a corelayer providing structural support.

Embodiment F1. An electrostatic sheet jamming apparatus comprising: afirst set of sheets, each of the first set of sheets comprising a firstconductive layer, a second set of sheets, each of the second set ofsheets comprising a second conductive layer, a first connectorelectrically conductively connected to the first conductive layers of atleast part of the first set of sheets, a second connector electricallyconductively connected to the second conductive layers of at least partof the second set of sheets, and a set of dielectric layers. The firstset of sheets are connected on two edges. The second set of sheets areconnected on two edges. The first set of sheets and the second set ofsheets are interdigitated, wherein each of the adjacent pair of thefirst set of sheets and the second set of sheets has one of the set ofdielectric layers disposed in between. The first set of sheets and thesecond set of sheets are movable relative to each other in a firststate. The first set of sheets and the second set of sheets are jammedwith each other in a second state when a voltage is applied between thefirst connector and the second connector.

Embodiment F2. The apparatus of Embodiment F1, wherein at least some ofdielectric layers are coated on the first set of sheets.

Embodiment F3. The apparatus of Embodiment F2, wherein at least some ofdielectric layers are coated on the second set of sheets.

Embodiment F4. The apparatus of any one of Embodiments F1-F3, whereinthe first set of sheets and the second set of sheets are interdigitatedwith an angle greater than 0 degree.

Embodiment F5. The apparatus of any one of Embodiments F1-F4, whereinthe first set of sheets are connected on two opposing edges.

Embodiment F6. The apparatus of any one of Embodiments F1-F5, whereinthe first set of sheets are connected on two adjacent edges.

Embodiment F7. The apparatus of Embodiment F6, wherein the second set ofsheets are connected on two adjacent edges.

Embodiment F8. The apparatus of Embodiment F7, wherein the first set ofsheets are rotatable relative to the second set of sheets in the firststate.

Embodiment F9. The apparatus of any one of Embodiments F1-F8, furthercomprising: one or more urging elements configured to keep the first setof sheets and the second set of sheets close to each other.

Embodiment F10. The apparatus of Embodiment F9, wherein the one or moreurging elements comprise at least one of a highly compliant outer layer,a highly compliant inner layer, a fixed clearance limiting element, anda spring element.

Embodiment F11. The apparatus of any one of Embodiments F1-F10, whereina distance between an adjacent pair of the first conductive layer andthe second conductive layer in the first state is no greater than 10micrometers.

Embodiment F12. The apparatus of any one of Embodiments F1-F11, whereina distance between an adjacent pair of the first conductive layer andthe second conductive layer in the first state is no greater than 5micrometers.

Embodiment F13. The apparatus of any one of Embodiments F1-F12, whereinat least one of the set of dielectric layers has a thickness less thanor equal to 10 micrometers.

Embodiment F14. The apparatus of any one of Embodiments F1-F13, whereinat least one of the set of dielectric layers has a thickness less thanor equal to 5 micrometers.

Embodiment F15. The apparatus of any one of Embodiments F1-F14, whereinthe applied voltage is no greater than 100V.

Embodiment F16. The apparatus of Embodiment F15, wherein the appliedvoltage is less than or equal to a break-down voltage of air at adistance between adjacent one of the first set of sheets and one of thesecond set of sheets.

Embodiment F17. The apparatus of any one of Embodiments F1-F16, whereinthe first set of sheets are separated from a large sheet having aconductive layer.

Embodiment F18. The apparatus of Embodiment F17, wherein the large sheetis a roll of sheet.

Embodiment F19. The apparatus of any one of Embodiments F1-F18, whereinat least one of the first set of sheets is patterned such that it isextensible in at least one axis.

Embodiment F20. The apparatus of any one of Embodiments F1-F19, whereinat least one of the first set of sheets has patterned openings such thatit is extensible in at least one axis.

Embodiment F21. The apparatus of any one of Embodiments F1-F20, whereinat least one of the first set of sheets has a plurality of protrudedfeatures.

Embodiment F22. The apparatus of Embodiment F21, wherein at least one ofthe first set of sheets has a plurality of protruded features.

Embodiment F23. The apparatus of Embodiment F22, wherein at least someof the plurality of protruded features of at least one of the first setof sheets are mated with some of the plurality of protruded features ofat least one of the second set of sheets in the second state.

Embodiment F24. The apparatus of any one of Embodiments F1-F23, whereinat least one of the set of dielectric layers has a relative permittivitygreater than 3.

Embodiment F25. The apparatus of any one of Embodiments F1-F24, whereinat least one of the set of dielectric layers comprises an inorganiccompound.

Embodiment F26. The apparatus of any one of Embodiments F1-F25, whereina coefficient of friction of at least one of the first set of sheets isless than 0.4.

Embodiment F27. The apparatus of any one of Embodiments F1-F26, whereinat least one of the first set of sheets comprises a core layer providingstructural support.

Embodiment G1. An electrostatic sheet jamming apparatus comprising afirst sheet comprising a first conductive layer, a first dielectriclayer disposed adjacent to the first conductive layer, a second sheetcomprising a second conductive layer and disposed proximate to the firstdielectric layer. The first dielectric layer is disposed between thefirst conductive layer and the second conductive layer. The first sheetand the second sheet are made of non-extensible materials and flexible.The first sheet comprises a set of first slit features such that thefirst sheet is extensible on a first axis. The second sheet comprises aset of second slit features such that the second sheet is extensible ona second axis. The first sheet and the second sheet are slidablerelative to each other in a first state. The first sheet and the secondsheet are locked against each other in a second state when a voltage isapplied between the first conductive layer and the second conductivelayer.

Embodiment G2. The apparatus of Embodiment G1, wherein the firstconductive layer is a coating on the first sheet.

Embodiment G3. The apparatus of Embodiment G1 or G2, wherein the firstdielectric layer is a coating on the first sheet.

Embodiment G4. The apparatus of any one of Embodiments G1-G3, whereinone of the set of first slit features is an elongated opening, atriangle opening, and an oval opening.

Embodiment G5. The apparatus of any one of Embodiments G1-G4, wherein atleast one of the first and second sheets are extensible in one axis.

Embodiment G6. The apparatus of any one of Embodiments G1-G5, wherein atleast one of the first and second sheets are extensible in more than oneaxis.

Embodiment G7. The apparatus of any one of Embodiments G1-G6, furthercomprising: one or more urging elements configured to keep the firstsheet and the second sheet close to each other.

Embodiment G8. The apparatus of Embodiment G7, wherein each of the oneor more urging elements comprises a highly compliant outer layer.

Embodiment G9. The apparatus of Embodiment G7, wherein each of the oneor more urging elements comprises a highly compliant inner layer.

Embodiment G10. The apparatus of Embodiment G7, wherein at least one ofthe one or more urging elements is made of a stretchable material.

Embodiment G11. The apparatus of any one of Embodiments G1-G10, whereinthe second axis is parallel to the first axis.

Embodiment G12. The apparatus of any one of Embodiments G1-G11, furthercomprising: a second dielectric layer coated on the second sheet.

Embodiment G13. The apparatus of any one of Embodiments G1-G12, whereinthe applied voltage is no greater than a break-down voltage of adistance between the first and the second conductive layer.

Embodiment G14. The apparatus of any one of Embodiments G1-G13, whereinthe applied voltage is no greater than 100V.

Embodiment G15. The apparatus of any one of Embodiments G1-G14, whereinthe first dielectric layer has a thickness less than or equal to 10micrometers.

Embodiment G16. The apparatus of any one of Embodiments G1-G15, whereinthe first dielectric layer has a thickness less than or equal to 5micrometers.

Embodiment G17. The apparatus of any one of Embodiments G1-G16, whereinthe first sheet is separated from a large sheet having a conductivelayer.

Embodiment G18. The apparatus of Embodiment G17, wherein the large sheetis a roll of sheet.

Embodiment G19. The apparatus of any one of Embodiments G1-G18, whereinthe first sheet is patterned such that it is extensible in at least oneaxis.

Embodiment G20. The apparatus of any one of Embodiments G1-G19, whereinthe first dielectric layer has a relative permittivity greater than 3.

Embodiment G21. The apparatus of any one of Embodiments G1-G20, whereinthe first dielectric layer comprises an inorganic compound.

Embodiment G22. The apparatus of any one of Embodiments G1-G21, whereinat least one of the first sheet and the second sheet comprises a corelayer providing structural support.

Embodiment H1. A flexible electronic device, comprising: a flexiblecomponent layer comprising at least one electronic component, and ajamming device disposed proximate to the flexible component layer. Thejamming device permits the flexible component layer to be bent in afirst state. The jamming device is configured to resist bending of theflexible component layer in a second state.

Embodiment H2. The electronic device of Embodiment H1, wherein thejamming device comprises a plurality of sheets.

Embodiment H3. The electronic device of Embodiment H2, wherein theplurality of sheets comprises conductive layers such that the jammingdevice are jammable electrostatically.

Embodiment H4. The electronic device of Embodiment H2, wherein thejamming device are jammable by a vacuum.

Embodiment H5. The electronic device of Embodiment H2, wherein at leastsome of the plurality of sheets are substantially conform to a primarysurface of the flexible component layer.

Embodiment H6. The electronic device of Embodiment H2, wherein at leastsome of the plurality of sheets are substantially perpendicular to aprimary surface of the flexible component layer.

Embodiment H7. The electronic device of any one of Embodiments H1-H6,wherein the electronic device is a display.

Embodiment H8. The electronic device of any one of Embodiments H1-H7,wherein the electronic device is a wearable electronic device.

Embodiment H9. The electronic device of Embodiment H3, wherein theplurality of sheets comprises a first set of sheets and a second set ofsheets, wherein the first set of sheets and the second set of sheets areinterdigitated, and wherein the second state is induced when a voltageis applied between the first set of sheets and the second set of sheets.

Embodiment H10. The electronic device of Embodiment H9, furthercomprising a set of dielectric layers.

Embodiment H11. The electronic device of Embodiment H10, wherein atleast some of the set of dielectric layers are coated on the first setof sheets.

Embodiment H12. The electronic device of Embodiment H11, wherein atleast some of the set of dielectric layers are coated on the second setof sheets.

Embodiment H13. The electronic device of any one of Embodiments H9-H12,wherein a distance between an adjacent pair of the first conductivelayer and the second conductive layer in the first state is no greaterthan 10 micrometers.

Embodiment H14. The electronic device of any one of Embodiments H9-H13,wherein the first dielectric layer covers less than one hundred percentof a circumference of the first sheet.

Embodiment H15. The electronic device of any one of Embodiments H9-H14,wherein the applied voltage is less than or equal to a break-downvoltage of air at a distance between adjacent one of the first set ofsheets and one of the second set of sheets.

Embodiment H16. The electronic device of any one of Embodiments H9-H15,wherein the applied voltage is no greater than 100V.

Embodiment H17. The electronic device of any one of Embodiments H9-H16,further comprising: one or more urging elements configured to keep thefirst set of sheets and the second set of sheets close to each other.

Embodiment H18. The electronic device of Embodiment H17, wherein the oneor more urging elements comprise at least one of a highly compliantouter layer, a highly compliant inner layer, a fixed clearance limitingelement, and a spring element.

Embodiment H19. The electronic device of any one of Embodiments H9-H18,wherein at least one of the set of dielectric layers has a thicknessless than or equal to 10 micrometers.

Embodiment H20. The electronic device of any one of Embodiments H9-H19,wherein at least one of the set of dielectric layers has a thicknessless than or equal to 5 micrometers.

Embodiment H21. The electronic device of any one of Embodiments H9-H20,wherein the first set of sheets are separated from a large sheet havinga conductive layer.

Embodiment H22. The electronic device of Embodiment H21, wherein thelarge sheet is a roll of sheet.

Embodiment H23. The electronic device of any one of Embodiments H2-H22,wherein at least one of the set of sheets is patterned such that the atleast one of the set of sheets is extensible in at least one axis.

Embodiment H24. The electronic device of any one of Embodiments H2-H23,wherein at least one of the first set of sheets has patterned openingssuch that it is extensible in at least one axis.

Embodiment H25. The electronic device of any one of Embodiments H9-H24,wherein at least one of the first set of sheets has a plurality ofprotruded features.

Embodiment H26. The electronic device of Embodiment H25, wherein atleast one of the second set of sheets has a plurality of protrudedfeatures.

Embodiment H27. The electronic device of Embodiment H26, wherein atleast some of the plurality of protruded features of at least one of thefirst set of sheets are mated with some of the plurality of protrudedfeatures of at least one of the second set of sheets in the secondstate.

Embodiment H28. The electronic device of Embodiment H10, wherein atleast one of the set of dielectric layers has a relative permittivitygreater than 3.

Embodiment H29. The electronic device of Embodiment H10, wherein atleast one of the set of dielectric layers comprises an inorganiccompound.

Embodiment H30. The electronic device of any one of Embodiments H2-H29,wherein a coefficient of friction of at least one of the set of sheetsis less than 0.4.

Embodiment H31. The electronic device of any one of Embodiments H2-H30,wherein at least one of the set of sheets comprises a core layerproviding structural support.

EXAMPLES Example 1

A roll of polyethylene terephthalate (PET) that was 0.002 inch (0.00508cm) thick was sputter coated with a 0.030 micrometer thick layer ofcopper on one side as a conductive layer, and then reactively sputtercoated with a 0.050 micrometer thick layer of silicon aluminum oxide asa dielectric layer over the copper layer. Eighteen sheets were cut fromthe roll into strips that were 6 inches (15.24 cm) wide by 15 inches(18.1 cm) long. The strips were combined into double sided electrostaticjamming sheets by placing sets of two sheets with the plain PET surfacestouching. The double sided electrostatic jamming sheets were thenassembled into two sets of interdigitated sheets as shown in FIG. 1F.The two sets of sheets were electrically and mechanically connectedtogether with conductive tape as shown in FIG. 1F. The strips were laidon a table with the long axis of one set perpendicular to the other setas shown in FIG. 8. One of the sets was then secured to the table, andtwo aluminum weights (total mass of 17.95 g) were placed on theintersection of the sets to urge them into proximity without excessivepressure. Varying voltages were applied between the sets of jammingsheets while the one set was pulled slowly with a Chatillon DFS-050digital force gauge (available at Ametek, Inc., Berwyn, Pa., UnitedStates). The average force required to pull the set was recorded. Setsof 3 trials were made at a voltage level and 3 trials at zero voltagewere made between each set of powered trials. The applied voltage andaverage resulting force for all the trials is summarized in Table 1.

TABLE 1 Trial set # Voltage (V) Average Force (N) 1 0 0.67 2 5 0.75 3 00.63 4 10 0.96 5 0 0.68 6 15 2.07 7 0 0.61 8 20 3.83 9 0 0.76

The results showed that a significant pressure can be achieved at verylow voltage levels. The consistent return to a low force at zero voltagedemonstrates that we have not created an electric field that is sostrong that it polarizes the materials or injects space charge into thesystem. The results match the model as discussed above well. They fitthe expected quadratic relationship with an R² value of 0.994. With anarea A of 36 square inch (232.258 cm²) and N=9 interfaces, we canestimate the coefficient of friction from the zero voltage data to beμ=0.044. The jamming pressure caused by electrostatic jamming at 20V isestimated to be about 416 Pa.

The present invention should not be considered limited to the particularexamples and embodiments described above, as such embodiments aredescribed in detail to facilitate explanation of various aspects of theinvention. Rather the present invention should be understood to coverall aspects of the invention, including various modifications,equivalent processes, and alternative devices falling within the spiritand scope of the invention as defined by the appended claims and theirequivalents.

What is claimed is:
 1. An electrostatic sheet jamming device formed by asheet having a conductive layer and a dielectric layer, comprising: afirst section of the sheet, the first section being separated from thesheet, a second section of the sheet, the second section being separatedfrom the sheet, wherein the sheet is non-extensible and flexible,wherein the first section and the second section are slidable relativeto each other in a first state, and wherein the first section and thesecond section are jammed with each other in a second state when avoltage is applied between a conductive layer of the first section and aconductive layer of the second section.
 2. The jamming device of claim1, wherein the applied voltage is less than or equal to a break-downvoltage of air at a distance between the first and the second conductivelayer.
 3. The jamming device of claim 1, wherein the applied voltage isno greater than 100V.
 4. The jamming device of claim 1, wherein adistance between the first section and the second section is no greaterthan 10 micrometers in the first state.
 5. The jamming device of claim1, wherein the sheet is packaged in a roll.
 6. The jamming device ofclaim 1, wherein a coefficient of friction of the sheet is less than0.4.
 7. The jamming device of claim 1, wherein the dielectric layer hasa thickness less than or equal to 5 micrometers.
 8. The jamming deviceof claim 1, wherein the sheet has patterned openings such that it isextensible in at least one axis.
 9. The jamming device of claim 1,wherein the sheet has a plurality of protruded features.
 10. The jammingdevice of claim 1, wherein the dielectric layer has a relativepermittivity greater than
 3. 11. A method, comprising: retrieving asheet having a conductive layer and a dielectric layer; separating afirst set of sections from the sheet; connecting the first set ofsections electrically via a first connector; separating a second set ofsections from the sheet; connecting the second set of sectionselectrically via a second connector; and assembling the first set ofsections and the second set of sections into a jamming device, whereinthe sheet is non-extensible and flexible, wherein the first set ofsections and the second set of sections are slidable relative to eachadjacent pair in a first state, wherein the first set of sections andthe second set of sections are jammed together in a second state when avoltage is applied between the first connector and the second connector.12. The method of claim 11, wherein the dielectric layer has a thicknessless than or equal to 10 micrometers.
 13. The method of claim 11,wherein the dielectric layer has a thickness less than or equal to 5micrometers.
 14. The method of claim 11, further comprising: assemblingthe first set of sections and the second set of sections with one ormore urging elements.
 15. The method of claim 14, wherein the one ormore urging elements comprise at least one of a highly compliant outerlayer, a highly compliant inner layer, a fixed clearance limitingelement, and a spring element.